1. Field of the Invention
The present invention relates to an automatic transmission of a vehicle, and more particularly to a shift stage display device for an automatic transmission of a vehicle adapted to allow a driver to distinguish shift stages of the automatic transmission while running.
2. Description of the Prior Art
Generally, an automatic transmission of a vehicle is mounted with a transmission control unit (hereinafter referred to as TCU) for automatically adjusting a transmission ratio according to running speed and load of the vehicle.
The TCU controls a plurality of clutches mounted at a gear train and a brake in an actuation or non-actuation state to thereby adjust revolution at an output terminal of a planetary gear device.
In adjusting the revolutions at the output terminal, the TCU receives output signals of various sensors variably output according to running states of a vehicle to output to a solenoid valve for adjusting hydraulic pressure of a plurality of clutches provided at a gear train and the brake; said a transmission ratio duty control signal for shifting an automatic transmission without shifting shock according to given program execution steps, such that the solenoid valve is duty controlled and controllably turned on and off.
When a driver manipulates a shift lever after applying power to vehicles for running the vehicle with an automatic transmission, a current position of the shift lever is displayed on a cluster panel mounted in front of the driver by way of communications according to the prior art, such that the driver can locate where the shift lever is situated.
However, there is a problem in the prior art in that the current position of the change lever is only displayed according to changes of the change lever, per se; by the driver, while shifting change states of an automatic transmission cannot be determined in a running car. There is another problem in that a rapid countermeasure cannot be taken when there occurs a shift stage hold state caused by malfunction of a vehicle while the vehicle is shifted.
There present invention is provided to solve the aforementioned problems, and it is an object of the present invention to provide a shift stage display device for an automatic transmission of vehicle adapted to allow a driver to easily recognize a shifting progressive state while the vehicle is running.